Inexpensive Treadmill with a Concave Platform

ABSTRACT

A treadmill includes a frame, two rollers, a platform and a belt. The rollers are supported on the frame. The platform is supported on the frame and formed with a concave upper face. The belt is wound around the rollers and formed with a lower section and an upper section supported on the concave upper face of the concave platform.

BACKGROUND OF INVENTION

1. Field of Invention

The present invention relates to a treadmill and, more particularly, to an inexpensive treadmill including a concave platform.

2. Related Prior Art

A conventional treadmill includes a frame, two rollers, a planar platform and a belt. The frame includes two lateral members in the form of rectilinear tubes corresponding to the planar platform. The rollers are supported on the lateral members of the frame. The planar platform is also supported on the lateral members of the frame between the rollers. The belt is wound around the rollers and formed with an upper section supported on the planar platform.

There has been devised another conventional treadmill including a frame, front and rear rollers, middle rollers and a belt. The frame includes two rectilinear lateral members. The front, rear and middle rollers are supported on the rectilinear lateral members of the frame. The belt is wound around the front and rear rollers, with an upper section supported on the middle rollers.

There has been devised another conventional treadmill including a frame, front and rear rollers, middle rollers and a belt. The frame includes two concave lateral members. The front, rear and middle rollers are supported on the concave lateral members of the frame. The belt is wound around the front and rear rollers, with an upper section supported on the middle rollers.

In the conventional treadmills including the middle rollers, the middle rollers are made of metal. The conventional treadmills including the middle rollers are expensive since metal is expensive and getting more expensive.

The present invention is therefore intended to obviate or at least alleviate the problems encountered in the prior art.

SUMMARY OF INVENTION

It is the primary objective of the present invention to provide an inexpensive treadmill with a concave platform.

To achieve the foregoing objectives, the treadmill includes a frame, two rollers, a platform and a belt. The rollers are supported on the frame. The platform is supported on the frame and formed with a concave upper face. The belt is wound around the rollers and formed with a lower section and an upper section supported on the concave upper face of the concave platform.

Other objectives, advantages and features of the present invention will be apparent from the following description referring to the attached drawings.

BRIEF DESCRIPTION OF DRAWINGS

The present invention will be described via detailed illustration of four embodiments referring to the drawings wherein:

FIG. 1 is a perspective view of a treadmill according to the first embodiment of the present invention;

FIG. 2 is a cross-sectional view of the treadmill shown in FIG. 1;

FIG. 3 is an enlarged cross-sectional view of the treadmill shown in FIG. 2;

FIG. 4 is a cross-sectional view of a treadmill according to the second embodiment of the present invention;

FIG. 5 is a cross-sectional view of a treadmill according to the third embodiment of the present invention; and

FIG. 6 is a cross-sectional view of a treadmill according to the fourth embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

Referring to FIGS. 1 to 3, a treadmill includes a frame 10, two rollers 12, a concave platform 30, a belt 20, upper guiding units, and lower guiding units 15 according to a first embodiment of the present invention. The frame 10 includes two lateral members 11. The lateral members 11 of the frame 10 are preferably concave tubes. A wheel 18 is supported on a bracket secured to a front end of each of the lateral members 11 of the frame 10. The wheels 18 are used for rolling on the ground or a floor for transporting the treadmill.

Two supporting elements 13 are connected to the frame 10. Each of the supporting elements 13 includes a horizontal section extending between two vertical sections each connected to a related one of the lateral members 11 of the frame 10. The horizontal sections of the supporting elements 13 are used for contact with the ground or floor for positioning the treadmill.

The rollers 12 are supported on the lateral members 11 of the frame 10. Each of the rollers 12 includes an end rotationally supported on one of the lateral members 11 of the frame 10 and an opposite end rotationally supported on the other lateral member 11 of the frame 10. One of the rollers 12 is preferably located between the brackets, which support the wheels 18.

The belt 20 is in the form of a loop wound around the rollers 12. An upper section of the belt 20 is shorter and lighter than a lower section of the belt 20. Without any guiding units, the upper section of the belt 20 would dangle from the rollers 12 less than the lower section of the belt 20 and hence suspend above the concave platform 30.

The upper guiding units are arranged in two series each connected to an upper face of a related one of the lateral members 11 of the frame 10 for contact with a margin of the upper section of the belt 20. Each series includes an adequate number of upper guiding units for pushing almost the entire upper section of the belt 20 against the concave platform 13. Each of the upper guiding units includes a rod 14 and a block. The rod 14 includes an end in contact with the related margin of the upper section of the belt 20 and an opposite end secured to the block by welding for example. The block is secured to the upper face of the related lateral member of the frame 10 by welding for example.

The lower guiding units 15 are arranged in two series each connected to a lower face of a related one of the lateral members 11 of the frame 10 for contact with a related one of two opposite margins of the lower section of the belt 20. Each of the lower guiding units 15 includes a first caster 16 in contact with an upper face of the lower section of the belt 20 and a second caster 17 in contact with a lower face of the lower section of the belt 20.

The concave platform 30 is made of an elastic material that is less expensive than metal. The concave platform 30 may be made of plastics, wood or another inexpensive elastic material. The concave platform 30 includes a concave upper face 31 directed toward a runner running on the treadmill and a convex lower face 32 opposite to the concave upper face 31. The concave platform 30 is preferably made of constant thickness, i.e., the distance between the concave upper and convex lower faces of the concave platform 30 is constant. By screws for example, the concave platform 30 is secured to positioning elements 19 secured to the lateral members 11 of the frame 10 by welding for example.

In use, the runner runs on the belt 20, which slides on the concave platform 30. The platform 30 takes the weight of the runner. Moreover, the platform 30 reduces impacts on the user's feet since it is made with a concave configuration and of an elastic material.

Referring to FIG. 4, there is shown a treadmill according to a second embodiment of the present invention. The second embodiment is like the first embodiment except including a wear-resistant layer 40 provided on the upper face 31 of the concave platform 30 by an adhesive for example. The wear-resistant layer 40 may be a piece of cloth, rubber, plastics, leather, or a coating, or a particle board. The wear-resistant layer 40 protects the concave platform 30 and extends the life of the concave platform 30.

Referring to FIG. 5, there is shown a treadmill according to a third embodiment of the present invention. The third embodiment is like the second embodiment except including a buffering layer 50 sandwiched between the wear-resistant layer 40 and the concave platform 30 by an adhesive for example. The buffering layer 50 is made of foam, a porous material or any other proper material. The buffering layer 50 enhances the ability of the concave platform 30 to reduce the impacts on the runner.

Referring to FIG. 6, there is shown a treadmill according to a fourth embodiment of the present invention. The fourth embodiment is like the third embodiment except that the wear-resistant layer 40 includes protrusive portions 41 formed on a lower face. The protrusive portions 41 of the wear-resistant layer 40 are bosses or ridges. The runner feels the protrusive portions 41 of the wear-resistant layer 40 through the belt 20 and has the feet messaged by them.

The present invention has been described via the detailed illustration of the embodiments. Those skilled in the art can derive variations from the embodiments without departing from the scope of the present invention. Hence, the embodiments shall not limit the scope of the present invention defined in the claims. 

1. A treadmill including: a frame; two rollers supported on the frame; a platform supported on the frame and formed with a concave upper face; and a belt wound around the rollers and formed with a lower section and an upper section supported on the upper face of the concave platform.
 2. The treadmill according to claim 1, wherein the platform includes a convex lower face opposite to the concave upper face.
 3. The treadmill according to claim 2, wherein the concave upper face of the platform is located at constant distance from the convex lower face of the platform.
 4. The treadmill according to claim 1, including a wear-resistant layer provided on the concave upper face of the platform.
 5. The treadmill according to claim 4, wherein the wear-resistant layer includes protrusive portions formed on a lower face.
 6. The treadmill according to claim 5, wherein the protrusive portions of the wear-resistant layer are bosses.
 7. The treadmill according to claim 5, wherein the protrusive portions of the wear-resistant layer are ridges.
 8. The treadmill according to claim 4, including a buffering layer provided between the platform and the wear-resistant layer. 